cig/carribean/script.py

'''

@author: olivier.massot, 2019
'''
import heapq
import sys


# TODO:
# * add an esquive manoeuvre / try to avoid cannonballs
# * if an enemy is near a mine, shoot the mine instead of the ship
# * find a way to change direction without slowing down if possible
# * avoid getting blocked by a side-by-side with an ennemy
# * improve the 'avoid' part of the 'fire_at_will' method
# * use a queue to choose the best shoot instead of a strict equality
# * why do mines explode when turning around?

debug = True

def log(*msg):
    if debug:
        print(*msg, file=sys.stderr)

current_turn = 0

class CollisionAlert(Exception):
    pass

class Queue():
    def __init__(self):
        self.items = []
    
    def __bool__(self):
        return bool(self.items)

    def __repr__(self):
        return str(self.items)

    def put(self, item, priority):
        heapq.heappush(self.items, (priority, item))

    def get(self):
        return heapq.heappop(self.items)[1]

    @classmethod
    def merge(cls, *args, reverse=False):
        q = cls()
        q.items = list(heapq.merge(*[a.items for a in args], key=lambda x: x[1], reverse=reverse))
        return q

class InterestQueue(Queue):
    def __add__(self, other):
        self.items += other.items
        return self
    
    def put(self, item):
        heapq.heappush(self.items, item)
        
    def get(self):
        return heapq.heappop(self.items)
    
    @classmethod
    def merge(cls, *args, reverse=False):
        q = cls()
        q.items = list(heapq.merge(*[a.items for a in args], reverse=reverse))
        return q
    
class ObjectivesQueue(InterestQueue):
    
    @classmethod
    def re_eval(cls, q, pos=None, d=None):
        new_q = cls()
        while q:
            o = q.get()
            o.eval(pos, d)
            new_q.put(o)
        return new_q
    
class Base():
    def __repr__(self):
        return f"<{self.__class__.__name__}: {self.__dict__}>"



class BaseObjective(Base):
    def __init__(self, target):
        self.target = target
        self.interest = 0

    def __lt__(self, other):
        return self.interest < other.interest

    def __repr__(self):
        return f"<{self.__class__.__name__}: target={self.target.id};int={self.interest})>"

    def eval(self, pos = None, d = None):
        self.distance = Grid.manhattan(pos, self.target.pos) if pos is not None else 0
        self.alignment = abs(Grid.diff_directions(Grid.direction_to(*pos, *self.target.pos), d)) if d is not None else 0
        self._compute_interest()
        
    def _compute_interest(self):
        self.interest = 7 * self.distance + 3 * self.alignment
        
class GetBarrel(BaseObjective):
    def _compute_interest(self):
        self.interest = 6 * self.distance + 9 * self.alignment + 3 * self.target.dispersal + self.target.mine_threat ** 2 - 36 * self.target.ennemy_near

class Attack(BaseObjective):
    def _compute_interest(self):
        self.interest = 7 * self.distance + 3 * self.alignment + self.target.stock // 4 - 20 * self.target.blocked_since

class PathNode(tuple):
    def __new__(self, x, y, parent=None):
        n = tuple.__new__(self, (x, y))
        n.parent = parent
        n.cost = 0
        n.orientation = 0
        return n
    
    def __repr__(self):
        return f"<{self[0]}, {self[1]}, c:{self.cost}, o:{self.orientation}>"

class Grid(Base):
    def __init__(self):
        self.w = 23
        self.h = 21
        
        self._neighbors = {}
        for x in range(-1, self.w + 1):
            for y in range(-1, self.h + 1):
                self.cache_neighbors(x, y)
 
        self.load_entities({})
        
    def __contains__(self, key):
        return 0 <= key[0] < self.w and 0 <= key[1] < self.h

    def __iter__(self):
        for item in ((x, y) for x in range(self.w) for y in range(self.h)):
            yield item

    # data
    
    def load_entities(self, entities):
        
        # special: mines too far from ships are not recorded but still exist
        ghost_mines = []
        if hasattr(self, "mines"):
            for m in self.mines:
                if not m.pos in [e.pos for e in entities.values() if type(e) is Mine]:
                    if all((self.manhattan(m.pos, ship.pos) > 5) for ship in self.owned_ships):
                        m.ghost = True
                        ghost_mines.append(m)

        self.entities = entities
        self.index = {}
        self.ships = []
        self.owned_ships = []
        self.ennemy_ships = []
        self.ships = []
        self.barrels = []
        self.mines = []
        self.cannonballs = []
        
        for e in list(entities.values()) + ghost_mines:
            self.index[e.pos] = e
            type_ = type(e)
            
            if type_ is Ship:
                self.ships.append(e)
                if e.owned:
                    self.owned_ships.append(e)
                else:
                    self.ennemy_ships.append(e)

            elif type_ is Barrel:
                self.barrels.append(e)

            elif type_ is Mine:
                self.mines.append(e)

            elif type_ is Cannonball:
                self.cannonballs.append(e)
                
        for s in self.owned_ships:
            s.allies = [other for other in self.owned_ships if other is not s]
        for s in self.ennemy_ships:
            s.allies = [other for other in self.ennemy_ships if other is not s]

        for s in self.ships:
            s.next_positions = s.next_pos_proba(4)

        self.update_moving_costs()
        
        grav_center = self.barrels_gravity_center()
        for b in self.barrels:
            b.dispersal = Grid.manhattan(grav_center, b.pos) if grav_center != None else 0
            b.mine_threat = any(type(self.at(*c)) is Mine for c in self.neighbors(*b.pos))
            b.ennemy_near = any(b.pos in e.next_area for e in self.ennemy_ships)
                
        for s in self.owned_ships:
            
            s._can_move = {c: (s.moving_cost(*c) < 1000) for c in [s.front, s.front_left, s.left, s.front_right,
                                                                  s.right, s.back_left, s.back_right]}
            s.objectives = ObjectivesQueue()
            s.ennemies = ObjectivesQueue()
            
            for b in self.barrels:
                obj = GetBarrel(b)
                obj.eval(s.next_pos if s.speed else s.prow, s.orientation)
                s.objectives.put(obj)
                
            for e in self.ennemy_ships:
                obj = Attack(e)
                obj.eval(s.next_pos, s.orientation)
                s.ennemies.put(obj)

    def at(self, x, y):
        try:
            return self.index[(x, y)]
        except KeyError:
            return None
        
    def collision_at(self, x, y):
        e = self.at(x, y)
        return type(e) in [Mine, Ship, Cannonball] or not (x, y) in self.__iter__()
        
    def barrels_gravity_center(self):
        wx, wy, wtotal = 0,0,0
        for b in self.barrels:
            wx += (b.x * b.amount) 
            wy += (b.y * b.amount)
            wtotal += b.amount
        return (wx // wtotal, wy // wtotal) if wtotal else None

    def update_moving_costs(self):
        base_costs = {}
        self.collisions = []
        
        for x in range(-1, self.w + 1):
            for y in range(-1, self.h + 1):
                base_costs[(x, y)] = 10 # base moving cost
                
        for x, y in base_costs:
            if x in (-1, self.w + 1) or y in (-1, self.h):
                base_costs[(x, y)] = 1000 # out of the map
            elif x in (0, self.w - 1) or y in (0, self.h - 1):
                base_costs[(x, y)] = 15 # borders are a little more expensive     
        
        for m in self.mines:
            for n in self.neighbors(*m.pos):
                base_costs[n] += 30
        for m in self.mines:
            base_costs[m.pos] += 1000
        for c in self.cannonballs:
            base_costs[c.pos] += (100 + (6 - c.countdown) * 200)
        
        for ship in self.ships:
            ship._moving_costs = {}
            ship._moving_costs.update(base_costs)
            for other in self.ships:
                if other is ship:
                    continue
                dist = self.manhattan(ship.pos, other.pos)
                if dist > 8:
                    continue
                if not other.speed:
                    for c in other.area:
                        ship._moving_costs[c] += 1000
                else:
                    for c in self.zone(other.next_pos, 4):
                        if c in other.next_positions[1]:
                            if other.next_positions[1][c] > 10:
                                ship._moving_costs[c] += 1000
                            else:
                                ship._moving_costs[c] += 100
                        else:
                            ship._moving_costs[c] += 20

    def shooting_spot(self, ship, target):
        shooting_spots = Queue()
        target_pos = target.next_pos if type(target) is Ship else target.pos
        
        for x, y in self.zone(target_pos, 10):
            if ship.moving_cost(x, y) > 100:
                continue
            if self.manhattan((x, y), target_pos) <= 2:
                continue
            
            interest = 0 # the lower the better
            
            interest += ship.moving_cost(x, y)
            
            # avoid cells too close from borders
            if not 3 < x < (self.w - 3):
                interest += 50
            if not 3 <= y < (self.h - 3):
                interest += 50
            
            diff = abs(Grid.direction_to(*ship.prow, x, y))
            if diff > 1:
                interest += 15 * abs(diff)
            
            # priorize spots at distance 5 from active ship
            interest += (10 * abs(5 - self.manhattan((x, y), ship.pos)))
            
            
            shooting_spots.put((x, y), interest)
        return shooting_spots.get()
    
    # geometrical algorithms
    @staticmethod
    def from_cubic(xu, yu, zu):
        return (zu, int(xu + (zu - (zu & 1)) / 2))

    @staticmethod
    def to_cubic(x, y):
        zu = x
        xu = int(y - (x - (x & 1)) / 2)
        yu = int(-xu - zu)
        return (xu, yu, zu)

    @staticmethod
    def manhattan(from_, to_):
        xa, ya = from_
        xb, yb = to_
        return abs(xa - xb) + abs(ya - yb) 

    def zone(self, center, radius):
        buffer = frozenset([center])
        for _ in range(0, radius):
            current = buffer
            for x, y in current:
                buffer |= frozenset(self.abs_neighbors(x, y))
        return [c for c in buffer if 0 <= c[0] < self.w and 0 <= c[1] < self.h]       

    @staticmethod
    def closest(from_, in_):
        return min(in_, key=lambda x: Grid.manhattan(from_, x.pos))

    @staticmethod
    def directions(y):
        if y % 2 == 0:
            return [(1, 0), (0, -1), (-1, -1), (-1, 0), (-1, 1), (0, 1)]
        else:
            return [(1, 0), (1,-1), (0,-1), (-1, 0), (0, 1), (1, 1)]

    @staticmethod
    def direction_to(x0, y0, x, y):
        dx, dy = (x - x0), (y - y0)
        if dx > 0:
            if dy == 0:
                return 0
            elif dy > 0:
                return 5
            else:
                return 1
        elif dx < 0:
            if dy == 0:
                return 3
            elif dy > 0:
                return 4
            else:
                return 2
        else:
            if dy > 0:
                return 5 if y0 % 2 == 0 else 4
            else:
                return 1 if y0 % 2 == 0 else 2

    @staticmethod
    def add_directions(d1, d2):
        d = d2 + d1
        if d < 0:
            d += 6
        elif d > 5:
            d -= 6
        return d
    
    @staticmethod
    def diff_directions(d1, d2):
        d = d2 - d1
        if d <= -3:
            d += 6
        elif d > 3:
            d -= 6
        return d
    
    @staticmethod
    def next_cell(x, y, d, repeat=1):
        for _ in range(repeat):
            dx, dy = Grid.directions(y)[d]
            x, y = x + dx, y + dy
        return x, y
    
    @staticmethod
    def symetry(d):
        return d + 3 if d < 3 else d - 3
    
    @staticmethod
    def abs_neighbors(x, y):
        return ((x + dx, y + dy) for dx, dy in Grid.directions(y))
    
    def cache_neighbors(self, xc, yc):
        self._neighbors[(xc, yc)] = [(x, y) for x, y in Grid.abs_neighbors(xc, yc) if 0 <= x < self.w and 0 <= y < self.h]

    def neighbors(self, x, y):
        try:
            return self._neighbors[(x, y)]
        except KeyError:
            self.cache_neighbors(x, y)
            return self._neighbors[(x, y)]
        
    def rotate(self, center, coordinates, rotations):
        if coordinates == [center] or rotations % 6 == 0:
            return coordinates
        x0, y0 = center
        xu0, yu0, zu0 = self.to_cubic(x0, y0)
        result = []

        for x, y in coordinates:
            xu, yu, zu = self.to_cubic(x, y)
            dxu, dyu, dzu = xu - xu0, yu - yu0, zu - zu0
            for _ in range(rotations):
                dxu, dyu, dzu = -dzu, -dxu, -dyu
            xru, yru, zru = dxu + xu0, dyu + yu0, dzu + zu0
            xr, yr = self.from_cubic(xru, yru, zru)
            result.append((xr, yr))
        return result

    # pathfinding
    def path(self, start, d0, target, moving_costs={}, inertia=0, incl_start=False, limit=10000):
        nodes = Queue()
        break_on, iteration = limit, 0
        broken = False
        
        inertia_path = []
        effective_start = start
        for _ in range(inertia):
            effective_start = self.next_cell(*effective_start, d0)
            n = PathNode(*effective_start)
            n.orientation = d0
            inertia_path.append(n)
        
        origin = PathNode(*effective_start)
        origin.orientation = d0
        
        nodes.put(origin, 0)
        neighbors = []

        while nodes:
            current = nodes.get()

            if current == target or broken:
                path = []
                previous = current
                while previous:
                    if previous != origin or incl_start:
                        path.insert(0, previous)
                    previous = previous.parent
                return inertia_path + path

            neighbors = self.neighbors(*current)

            for x, y in neighbors:
                
                if (x, y) == current.parent:
                    continue
                
                iteration += 1
                if break_on > 0 and iteration >= break_on:
                    broken = True
                    break
                
                moving_cost = moving_costs.get((x, y), 1000)
                if moving_cost >= 1000:
                    continue
                
                d = Grid.direction_to(*current, x, y)
                diff = abs(Grid.diff_directions(current.orientation, d))
                if diff > 1:
                    # change direction one degree at a time
                    continue
                    
                if any(moving_costs.get(c, 1000) >= 1000 for c in Ship.get_area(x, y, d)):
                    continue
                    
                cost = current.cost + moving_cost + diff * 10
                    
                if (x, y) == effective_start and d == d0:
                    # prefer to go right at start
                    cost -= 10
                
                priority = cost + 10 * Grid.manhattan((x, y), target)

                node = PathNode(x, y, current)
                node.cost = cost
                node.orientation = d
                nodes.put(node, priority)
        else:
            return None

class Entity(Base):
    def __init__(self, ent_id):
        self.id = int(ent_id)
        self.x, self.y = 0, 0
        self.args = [0,0,0,0]

    def update(self, x, y, *args):
        self.x, self.y = int(x), int(y)
        
    @property
    def pos(self):
        return (self.x, self.y)
    
    def __lt__(self, other):
        # default comparison, used to avoid errors when used with queues and priorities are equals
        return self.id < other.id
    
    
class Position(Base):
    def __init__(self, pos, d, speed):
        self.pos = pos
        self.d = d
        self.speed = speed
    
class Ship(Entity):
    MAX_SPEED = 2
    SCOPE = 10
    
    SLOW_DOWN = 1
    SPEED_UP = 2
    TURN_LEFT = 3
    TURN_RIGHT = 4
    MOVES = [SLOW_DOWN, SPEED_UP, TURN_LEFT, TURN_RIGHT]
    COMMANDS = {SLOW_DOWN: "SLOWER", SPEED_UP: "FASTER", TURN_LEFT: "PORT", TURN_RIGHT: "STARBOARD", None: "NONE"}
    
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.x, self.y = 0, 0
        self.orientation = 0
        self.speed = 0
        self.stock = 0
        self.owned = 0
        
        self.next_cell = None
        self.next_pos = None
        self.last_fire = None
        self.last_mining = None
        self.blocked_since = 0
        self.same_traject_since = 0
        self.last_action = ""
        self.allies = []
        self._moving_costs = {}
        
        self.objectives = ObjectivesQueue()
        self.ennemies = ObjectivesQueue()
        
        self.objective = None
        self.objectives_next = []
        self.target_ennemy = None
        
        self.path = []
        
        self.distance = 0
        self.alignment = 0
        
    def __repr__(self):
        return f"<Ship {self.id}: pos=({self.x}, {self.y}), orientation={self.orientation}, speed={self.speed}, blocked={self.blocked_since}, last_fire={self.last_fire}, next_pos={self.next_pos}, area={self.area}>"

    def update(self, x, y, *args):
        previous_state = self.state()
        previous_traject = self.traject()
        
        super().update(x, y)
        self.orientation, self.speed, self.stock, self.owned = map(int, args)

        self.objectives = ObjectivesQueue()
        self.ennemies = ObjectivesQueue()
        
        self.objective = None
        self.objectives_next = []
        self.target_ennemy = None
        
        self.goto = None
        self.path = []
        self.next_positions = {}
        
        self.area = Ship.get_area(self.x, self.y, self.orientation)
        self.prow, _, self.stern = self.area
        
        self.next_cell = self.get_next_cell()
        self.next_pos = self.get_next_pos()
        self.next_area = Ship.get_area(*self.next_pos, self.orientation)
        
        self.front = Grid.next_cell(*self.prow, self.orientation)
        self.front_left = Grid.next_cell(*self.prow, Grid.add_directions(self.orientation, 1))
        self.left = Grid.next_cell(*self.prow, Grid.add_directions(self.orientation, 2))
        self.front_right = Grid.next_cell(*self.prow, Grid.add_directions(self.orientation, -1))
        self.right = Grid.next_cell(*self.prow, Grid.add_directions(self.orientation, -2))
        self.back_left = Grid.next_cell(*self.stern, Grid.add_directions(self.orientation, 1))
        self.back_right = Grid.next_cell(*self.stern, Grid.add_directions(self.orientation, -1))
        
        self._can_move = {}
        
        self.mobility_zone = list(set(self.area + self.next_area))
            
        if self.traject() != previous_traject:
            self.same_traject_since += 1
        else:
            self.same_traject_since = 0
    
        if self.state() == previous_state:
            self.blocked_since += 1
        else:
            self.blocked_since = 0

    def traject(self):
        return (self.orientation, self.speed)

    def state(self):
        return (self.x, self.y, self.orientation, self.speed)

    @classmethod
    def get_pos_in(cls, current, speed, orientation, in_=1):
        return Grid.next_cell(*current, orientation, repeat=speed * in_)

    @classmethod
    def get_area(cls, x, y, orientation):
        prow = Grid.next_cell(x, y, orientation)
        stern = Grid.next_cell(x, y, Grid.add_directions(orientation, 3))
        return [prow, (x, y), stern]

    def get_next_pos(self, in_=1):
        return self.get_pos_in(self.pos, self.speed, self.orientation, in_)
    
    def next_pos_proba(self, in_=1):

        # guess next positions
        positions = {0: [Position(self.pos, self.orientation, self.speed)]}
        
        for i in range(in_):
            
            positions[i + 1] = []
            
            for p in positions[i]:
                
                pos, d, speed = p.pos, p.d, p.speed
                
                # next pos with inertia
                inertia = Grid.next_cell(*pos, d, repeat=speed)
                
                # wait (or fire or mine)
                positions[i + 1].append(Position(inertia, d, speed))
                
                # turn left
                positions[i + 1].append(Position(inertia, Grid.add_directions(d, 1), speed))
                    
                # turn right
                positions[i + 1].append(Position(inertia, Grid.add_directions(d, -1), speed))
                    
                # speed up
                if speed < self.MAX_SPEED:
                    positions[i + 1].append(Position(Grid.next_cell(*pos, d, repeat=speed + 1), d, speed + 1))
                
                # slow down
                if speed > 1:
                    positions[i + 1].append(Position(Grid.next_cell(*pos, d, repeat=speed - 1), d, speed - 1))
        
                # we voluntary ignore the case where a ship at speed 1 would slow down, 
                # as it is not expected to be a standard behaviour for a ship
        
        # agregate
        proba = {}
        for i, plst in positions.items():
            proba[i] = {}
            for p in plst:
                for c in Ship.get_area(*p.pos, p.d):
                    if self.moving_cost(*c) >= 1000:
                        continue
                    proba[i][c] = proba[i].get(c, 0) + 10
        
        # involve the moving cost
        for i in proba:
            for c in proba[i]:
                proba[i][c] -= (self.moving_cost(*c) // 2)
        
            # if ship is blocked, current area is more accurate
            for c in self.area:
                proba[i][c] = proba[i].get(c, 0) + 40 * self.blocked_since
        
        return proba
    
    def guess_next_positions(self, in_=3):
        proba = self.next_pos_proba(in_)
        best = {}
        for i in proba:
            best[i] = max(proba[i].items(), key=lambda x: x[1])[0]
        return best
            
    def get_next_cell(self, in_=1):
        return Grid.next_cell(self.x, self.y, self.orientation, repeat=in_)

    def in_current_direction(self, x, y):
        return self.orientation == Grid.direction_to(*self.pos, x, y)

    def moving_cost(self, x, y):
        return self._moving_costs.get((x, y), 1000)
    
    def can_turn_left(self):
        return self._can_move[self.left] and self._can_move[self.back_right]
    
    def can_turn_right(self):
        return self._can_move[self.right] and self._can_move[self.back_left]
    
    def can_move_fwd(self):
        return self._can_move[self.front]
    
    def can_move(self):
        return self.can_move_fwd() or self.can_turn_left() or self.can_turn_left()
    
    def move(self, path):
            
        if path:
            planned = self._plan_move(path)
            
        if path is None:
            if self.can_move():
                if self.can_move_fwd():
                    planned = Ship.SPEED_UP
                elif self.can_turn_left():
                    planned = Ship.TURN_LEFT
                elif self.can_turn_right():
                    planned = Ship.TURN_RIGHT
                log(f"(!) broken: automove ({planned})")
            else:
                log(f"(!) broken: can not move")
                return False
#             if self.can_move():
#                 
#                 self.auto_move(*self.goto)
#                 return True
#             else:
#                 return False
        elif not path:
            return False
        
        next_move = planned
        available_moves = [next_move] + [m for m in Ship.MOVES if m != planned]
        
        for move in available_moves:
            
            new_speed = self.speed
            new_orientation = self.orientation
            if move == Ship.SPEED_UP:
                new_speed += 1
            elif move == Ship.SLOW_DOWN:
                new_speed -= 1
            elif move == Ship.TURN_LEFT:
                new_orientation = Grid.add_directions(self.orientation, 1)
            elif move == Ship.TURN_RIGHT:
                new_orientation = Grid.add_directions(self.orientation, -1)
            
            new_pos = self.get_next_cell(new_speed)
            new_area = self.get_area(*new_pos, new_orientation)
    
            log([(c, self.moving_cost(*c)) for c in new_area])
    
            # special: extra-grid cells are not consider as collisions since a part of the ship can go there
            if any((self.moving_cost(*c) >= 1000 and c in grid) for c in new_area):
                log(f"/!\ Danger: planned move <{Ship.COMMANDS[move]}> would lead to collision")
            else:
                next_move = move
                break
        else:
            log("* No collision-free move was found, go to the initial one")
            
        if next_move == Ship.SPEED_UP:
            self.speed_up()
        elif next_move == Ship.SLOW_DOWN:
            self.slow_down()
        elif next_move == Ship.TURN_LEFT:
            self.turn_left()
        elif next_move == Ship.TURN_RIGHT:
            self.turn_right()
        else:
            return False

        return True

    def _plan_move(self, path):
        
        # flags represent direction changes or end of the path
        last_flag = len(path) - 1
        next_flag = next((i for i, n in enumerate(path) if n.orientation != self.orientation), last_flag)
        afternext_flag = next((i for i, n in enumerate(path[next_flag:]) if n.orientation != path[next_flag].orientation), last_flag)
        
        if not self.speed:
            diff = Grid.diff_directions(self.orientation, path[0].orientation)
            
            if diff > 0 and self.last_action == "STARBOARD" or diff < 0 and self.last_action == "PORT":
                # special: avoid the starting hesitation
                return Ship.SPEED_UP
            
            if diff and next_flag == 0:
                # start, with a direction change
                if diff > 0:
                    if self.can_turn_left():
                        return Ship.TURN_LEFT
                elif diff < 0:
                    if self.can_turn_right():
                        return Ship.TURN_RIGHT
                    
            # start straight
            if self.can_move_fwd():
                return Ship.SPEED_UP
        
        elif self.speed == self.MAX_SPEED:
            
            if self.speed == next_flag and afternext_flag >= (next_flag + 2): # there is at least one straight cell after this drift
                # drift
                diff = Grid.diff_directions(self.orientation, path[next_flag].orientation)
                if diff > 0:
                    return Ship.TURN_LEFT
                elif diff < 0:
                    return Ship.TURN_RIGHT
            
            if (self.speed + 1) >= next_flag:
                # next direction change or target will be passed at current speed
                return Ship.SLOW_DOWN

        elif self.speed == 1:
            
            if self.speed == next_flag:
                diff = Grid.diff_directions(self.orientation, path[next_flag].orientation)
                if diff > 0:
                    return Ship.TURN_LEFT
                elif diff < 0:
                    return Ship.TURN_RIGHT
            
            elif next_flag > 3 or (next_flag > 2 and afternext_flag >= (next_flag + 2)):
                return Ship.SPEED_UP
        
        return None
           
    def fire_at_will(self, *args, **kwargs):
        return self._fire_at_will(*args, **kwargs)
           
    def _fire_at_will(self, target, allies = []):
        if not self.can_fire():
            return False
        
        avoid = []
        if not self in allies:
            allies.append(self)
        for ally in allies:
            avoid += ally.mobility_zone
        
        next_positions = target.guess_next_positions(in_=4)
        for t, next_pos in next_positions.items():
            dist = Grid.manhattan(self.prow, next_pos)
            if dist > self.SCOPE:
                continue
            if next_pos in avoid:
                continue
            
            dt = 1 + (1 + round(dist / 3)) # time for the cannonball to reach this pos (including fire turn)
            
            if dt == t:
                log(f"[x] precise shoot: dt={dt}, pos={next_pos}")
                ship.fire(*next_pos)
                return True
            
        # give a try
        next_pos = next_positions[2]
        if not next_pos in avoid:
            dist_p = Grid.manhattan(self.prow, next_pos)
            if dist_p <= self.SCOPE:
                ship.fire(*next_pos)
                return True
            
        return False
        
    def can_mine(self):
        return self.last_mining is None or (current_turn - self.last_mining) >= 4
        
    def can_fire(self):
        return self.last_fire is None or (current_turn - self.last_fire) >= 1
            
    # --- Basic commands
    def _act(self, cmd, *args):
        self.last_action = cmd
        output = " ".join([cmd] + [str(a) for a in args])
        log(f"ship {self.id}: {output}")
        print(output)
    
    def auto_move(self, x, y):
        self._act("MOVE", x, y)
        
    def speed_up(self):
        self._act("FASTER")
        
    def slow_down(self):
        self._act("SLOWER")    
    
    def turn_right(self):
        self._act("STARBOARD")
    
    def turn_left(self):
        self._act("PORT")
        
    def wait(self):
        self._act("WAIT")
        
    def mine(self):
        self.last_mining = current_turn
        self._act("MINE")
        
    def fire(self, x, y):
        self.last_fire = current_turn
        self._act("FIRE", x, y)

class Barrel(Entity):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.amount = 0

        self.dispersal = 0
        self.mine_threat = False
        self.ennemy_near = False

    def __repr__(self):
        return f"<Barrel {self.id}: pos=({self.x}, {self.y}), amount={self.amount}>"
        
    def update(self, x, y, *args):
        super().update(x, y)
        self.amount = int(args[0])

class Mine(Entity):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.ghost = False

    def __repr__(self):
        return f"<Mine {self.id}: pos=({self.x}, {self.y}), ghost={self.ghost}>"

class Cannonball(Entity):

    def update(self, x, y, *args):
        super().update(x, y)
        self.sender, self.countdown = int(args[0]), int(args[1])


entities = {}
map_entity = {"SHIP": Ship, 
             "BARREL": Barrel,
             "MINE": Mine,
             "CANNONBALL": Cannonball}

grid = Grid()



### *** Main Loop ***

while True:
    seen = []
    current_turn += 1
    
    # <--- get input
    my_ship_count, entity_count = int(input()), int(input())
    previous_ent, entities = grid.entities, {}
    for _ in range(entity_count):
        ent_id, ent_type, *data = input().split()
        ent_id = int(ent_id)
        entities[ent_id] = grid.entities.get(ent_id, map_entity[ent_type](ent_id))
        entities[ent_id].update(*data)
    # --->
    
    grid.load_entities(entities)
    
    log(f"### TURN {current_turn}")
    
#     log(f"Owned Ships: {grid.owned_ships}")
    log(f"Ennemy Ships: {grid.ennemy_ships}")
    log(f"Barrels: {grid.barrels}")
#     log(f"Mines: {grid.mines}")
    log(f"Cannonballs: {grid.cannonballs}")
    
    max_it = 6000 // len(grid.owned_ships)

    ### Acquire
    log("# Acquiring")
    
    # main objective
    while not all(s.objective for s in grid.owned_ships):
        try:
            acquired = sorted([(s, s.objectives.get()) for s in grid.owned_ships if not s.objective], key= lambda x: x[1].interest)
            
            for s, o in acquired:
                if not s.objective and not any(al.objective.target is o.target for al in s.allies if al.objective):
                    s.objective = o
            
        except IndexError:
            break
        
    # targetted ennemy
    for s in grid.owned_ships:
        s.target_ennemy = s.ennemies.get()
        
    ### Plan
    log("# Planning")
    
    for ship in grid.owned_ships:
        it_consumed = 0
        
        if ship.objective:
            ship.goto = ship.objective.target.pos
        elif ship.target_ennemy:
            ship.goto = grid.shooting_spot(ship, ship.target_ennemy.target)
        else:
            log("ERROR: No target")
            continue
        
        ship.path = grid.path(ship.pos, 
                              ship.orientation, 
                              ship.goto, 
                              moving_costs=ship._moving_costs, 
                              inertia=ship.speed, 
                              limit=(max_it - it_consumed))
        
        if ship.objective and ship.path:
            while ship.objectives and len(ship.path) < 10:
                pos, d = ship.path[-1], ship.path[-1].orientation
                
                ship.objectives = ObjectivesQueue.re_eval(ship.objectives, pos, d)
                current_obj = ship.objectives.get()
                
                ship.objectives_next.append(current_obj)
            
                new_path = grid.path(pos, d, 
                                       current_obj.target.pos, 
                                       ship._moving_costs,
                                       limit=(max_it - it_consumed)) or []
                if new_path:
                    ship.path += new_path
                else:
                    break
 
    for ship in grid.owned_ships:
        log(f"---- ship {ship.id} ---")
        log(f"ship: {ship}")
        log(f"obj: {ship.objective}; next: {ship.objectives_next}")
        log(f"target: {ship.target_ennemy}")
        log(f"goto: {ship.goto}")
        log(f"path: {ship.path}")
        
    ### Process
    log("# Processing")
    
    for ship in grid.owned_ships:
        log(f"---- ship {ship.id} ---")
        if not ship.objective and not ship.target_ennemy:
            log("No target: wait")
            ship.wait()
        
        if ship.move(ship.path):
            continue
        
        # no movement was required, can fire
        if ship.fire_at_will(ship.target_ennemy.target, allies=grid.owned_ships):
            continue
        
        log("ERROR: Did not act, wait")
        ship.wait()